[linux-block.git] / drivers / char / mspec.c

/*
 * Copyright (C) 2001-2006 Silicon Graphics, Inc.  All rights
 * reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2 of the GNU General Public License
 * as published by the Free Software Foundation.
 */

/*
 * SN Platform Special Memory (mspec) Support
 *
 * This driver exports the SN special memory (mspec) facility to user
 * processes.
 * There are three types of memory made available thru this driver:
 * fetchops, uncached and cached.
 *
 * Fetchops are atomic memory operations that are implemented in the
 * memory controller on SGI SN hardware.
 *
 * Uncached are used for memory write combining feature of the ia64
 * cpu.
 *
 * Cached are used for areas of memory that are used as cached addresses
 * on our partition and used as uncached addresses from other partitions.
 * Due to a design constraint of the SN2 Shub, you can not have processors
 * on the same FSB perform both a cached and uncached reference to the
 * same cache line.  These special memory cached regions prevent the
 * kernel from ever dropping in a TLB entry and therefore prevent the
 * processor from ever speculating a cache line from this page.
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/miscdevice.h>
#include <linux/spinlock.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/vmalloc.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/numa.h>
#include <linux/refcount.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <linux/atomic.h>
#include <asm/tlbflush.h>
#include <asm/uncached.h>
#include <asm/sn/addrs.h>
#include <asm/sn/arch.h>
#include <asm/sn/mspec.h>
#include <asm/sn/sn_cpuid.h>
#include <asm/sn/io.h>
#include <asm/sn/bte.h>
#include <asm/sn/shubio.h>


#define FETCHOP_ID	"SGI Fetchop,"
#define CACHED_ID	"Cached,"
#define UNCACHED_ID	"Uncached"
#define REVISION	"4.0"
#define MSPEC_BASENAME	"mspec"

/*
 * Page types allocated by the device.
 */
enum mspec_page_type {
	MSPEC_FETCHOP = 1,
	MSPEC_CACHED,
	MSPEC_UNCACHED
};

#ifdef CONFIG_SGI_SN
static int is_sn2;
#else
#define is_sn2		0
#endif

/*
 * One of these structures is allocated when an mspec region is mmaped. The
 * structure is pointed to by the vma->vm_private_data field in the vma struct.
 * This structure is used to record the addresses of the mspec pages.
 * This structure is shared by all vma's that are split off from the
 * original vma when split_vma()'s are done.
 *
 * The refcnt is incremented atomically because mm->mmap_sem does not
 * protect in fork case where multiple tasks share the vma_data.
 */
struct vma_data {
	refcount_t refcnt;	/* Number of vmas sharing the data. */
	spinlock_t lock;	/* Serialize access to this structure. */
	int count;		/* Number of pages allocated. */
	enum mspec_page_type type; /* Type of pages allocated. */
	unsigned long vm_start;	/* Original (unsplit) base. */
	unsigned long vm_end;	/* Original (unsplit) end. */
	unsigned long maddr[0];	/* Array of MSPEC addresses. */
};

/* used on shub2 to clear FOP cache in the HUB */
static unsigned long scratch_page[MAX_NUMNODES];
#define SH2_AMO_CACHE_ENTRIES	4

static inline int
mspec_zero_block(unsigned long addr, int len)
{
	int status;

	if (is_sn2) {
		if (is_shub2()) {
			int nid;
			void *p;
			int i;

			nid = nasid_to_cnodeid(get_node_number(__pa(addr)));
			p = (void *)TO_AMO(scratch_page[nid]);

			for (i=0; i < SH2_AMO_CACHE_ENTRIES; i++) {
				FETCHOP_LOAD_OP(p, FETCHOP_LOAD);
				p += FETCHOP_VAR_SIZE;
			}
		}

		status = bte_copy(0, addr & ~__IA64_UNCACHED_OFFSET, len,
				  BTE_WACQUIRE | BTE_ZERO_FILL, NULL);
	} else {
		memset((char *) addr, 0, len);
		status = 0;
	}
	return status;
}

/*
 * mspec_open
 *
 * Called when a device mapping is created by a means other than mmap
 * (via fork, munmap, etc.).  Increments the reference count on the
 * underlying mspec data so it is not freed prematurely.
 */
static void
mspec_open(struct vm_area_struct *vma)
{
	struct vma_data *vdata;

	vdata = vma->vm_private_data;
	refcount_inc(&vdata->refcnt);
}

/*
 * mspec_close
 *
 * Called when unmapping a device mapping. Frees all mspec pages
 * belonging to all the vma's sharing this vma_data structure.
 */
static void
mspec_close(struct vm_area_struct *vma)
{
	struct vma_data *vdata;
	int index, last_index;
	unsigned long my_page;

	vdata = vma->vm_private_data;

	if (!refcount_dec_and_test(&vdata->refcnt))
		return;

	last_index = (vdata->vm_end - vdata->vm_start) >> PAGE_SHIFT;
	for (index = 0; index < last_index; index++) {
		if (vdata->maddr[index] == 0)
			continue;
		/*
		 * Clear the page before sticking it back
		 * into the pool.
		 */
		my_page = vdata->maddr[index];
		vdata->maddr[index] = 0;
		if (!mspec_zero_block(my_page, PAGE_SIZE))
			uncached_free_page(my_page, 1);
		else
			printk(KERN_WARNING "mspec_close(): "
			       "failed to zero page %ld\n", my_page);
	}

	kvfree(vdata);
}

/*
 * mspec_fault
 *
 * Creates a mspec page and maps it to user space.
 */
static vm_fault_t
mspec_fault(struct vm_fault *vmf)
{
	unsigned long paddr, maddr;
	unsigned long pfn;
	pgoff_t index = vmf->pgoff;
	struct vma_data *vdata = vmf->vma->vm_private_data;

	maddr = (volatile unsigned long) vdata->maddr[index];
	if (maddr == 0) {
		maddr = uncached_alloc_page(numa_node_id(), 1);
		if (maddr == 0)
			return VM_FAULT_OOM;

		spin_lock(&vdata->lock);
		if (vdata->maddr[index] == 0) {
			vdata->count++;
			vdata->maddr[index] = maddr;
		} else {
			uncached_free_page(maddr, 1);
			maddr = vdata->maddr[index];
		}
		spin_unlock(&vdata->lock);
	}

	if (vdata->type == MSPEC_FETCHOP)
		paddr = TO_AMO(maddr);
	else
		paddr = maddr & ~__IA64_UNCACHED_OFFSET;

	pfn = paddr >> PAGE_SHIFT;

	return vmf_insert_pfn(vmf->vma, vmf->address, pfn);
}

static const struct vm_operations_struct mspec_vm_ops = {
	.open = mspec_open,
	.close = mspec_close,
	.fault = mspec_fault,
};

/*
 * mspec_mmap
 *
 * Called when mmapping the device.  Initializes the vma with a fault handler
 * and private data structure necessary to allocate, track, and free the
 * underlying pages.
 */
static int
mspec_mmap(struct file *file, struct vm_area_struct *vma,
					enum mspec_page_type type)
{
	struct vma_data *vdata;
	int pages, vdata_size;

	if (vma->vm_pgoff != 0)
		return -EINVAL;

	if ((vma->vm_flags & VM_SHARED) == 0)
		return -EINVAL;

	if ((vma->vm_flags & VM_WRITE) == 0)
		return -EPERM;

	pages = vma_pages(vma);
	vdata_size = sizeof(struct vma_data) + pages * sizeof(long);
	if (vdata_size <= PAGE_SIZE)
		vdata = kzalloc(vdata_size, GFP_KERNEL);
	else
		vdata = vzalloc(vdata_size);
	if (!vdata)
		return -ENOMEM;

	vdata->vm_start = vma->vm_start;
	vdata->vm_end = vma->vm_end;
	vdata->type = type;
	spin_lock_init(&vdata->lock);
	refcount_set(&vdata->refcnt, 1);
	vma->vm_private_data = vdata;

	vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
	if (vdata->type == MSPEC_FETCHOP || vdata->type == MSPEC_UNCACHED)
		vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
	vma->vm_ops = &mspec_vm_ops;

	return 0;
}

static int
fetchop_mmap(struct file *file, struct vm_area_struct *vma)
{
	return mspec_mmap(file, vma, MSPEC_FETCHOP);
}

static int
cached_mmap(struct file *file, struct vm_area_struct *vma)
{
	return mspec_mmap(file, vma, MSPEC_CACHED);
}

static int
uncached_mmap(struct file *file, struct vm_area_struct *vma)
{
	return mspec_mmap(file, vma, MSPEC_UNCACHED);
}

static const struct file_operations fetchop_fops = {
	.owner = THIS_MODULE,
	.mmap = fetchop_mmap,
	.llseek = noop_llseek,
};

static struct miscdevice fetchop_miscdev = {
	.minor = MISC_DYNAMIC_MINOR,
	.name = "sgi_fetchop",
	.fops = &fetchop_fops
};

static const struct file_operations cached_fops = {
	.owner = THIS_MODULE,
	.mmap = cached_mmap,
	.llseek = noop_llseek,
};

static struct miscdevice cached_miscdev = {
	.minor = MISC_DYNAMIC_MINOR,
	.name = "mspec_cached",
	.fops = &cached_fops
};

static const struct file_operations uncached_fops = {
	.owner = THIS_MODULE,
	.mmap = uncached_mmap,
	.llseek = noop_llseek,
};

static struct miscdevice uncached_miscdev = {
	.minor = MISC_DYNAMIC_MINOR,
	.name = "mspec_uncached",
	.fops = &uncached_fops
};

/*
 * mspec_init
 *
 * Called at boot time to initialize the mspec facility.
 */
static int __init
mspec_init(void)
{
	int ret;
	int nid;

	/*
	 * The fetchop device only works on SN2 hardware, uncached and cached
	 * memory drivers should both be valid on all ia64 hardware
	 */
#ifdef CONFIG_SGI_SN
	if (ia64_platform_is("sn2")) {
		is_sn2 = 1;
		if (is_shub2()) {
			ret = -ENOMEM;
			for_each_node_state(nid, N_ONLINE) {
				int actual_nid;
				int nasid;
				unsigned long phys;

				scratch_page[nid] = uncached_alloc_page(nid, 1);
				if (scratch_page[nid] == 0)
					goto free_scratch_pages;
				phys = __pa(scratch_page[nid]);
				nasid = get_node_number(phys);
				actual_nid = nasid_to_cnodeid(nasid);
				if (actual_nid != nid)
					goto free_scratch_pages;
			}
		}

		ret = misc_register(&fetchop_miscdev);
		if (ret) {
			printk(KERN_ERR
			       "%s: failed to register device %i\n",
			       FETCHOP_ID, ret);
			goto free_scratch_pages;
		}
	}
#endif
	ret = misc_register(&cached_miscdev);
	if (ret) {
		printk(KERN_ERR "%s: failed to register device %i\n",
		       CACHED_ID, ret);
		if (is_sn2)
			misc_deregister(&fetchop_miscdev);
		goto free_scratch_pages;
	}
	ret = misc_register(&uncached_miscdev);
	if (ret) {
		printk(KERN_ERR "%s: failed to register device %i\n",
		       UNCACHED_ID, ret);
		misc_deregister(&cached_miscdev);
		if (is_sn2)
			misc_deregister(&fetchop_miscdev);
		goto free_scratch_pages;
	}

	printk(KERN_INFO "%s %s initialized devices: %s %s %s\n",
	       MSPEC_BASENAME, REVISION, is_sn2 ? FETCHOP_ID : "",
	       CACHED_ID, UNCACHED_ID);

	return 0;

 free_scratch_pages:
	for_each_node(nid) {
		if (scratch_page[nid] != 0)
			uncached_free_page(scratch_page[nid], 1);
	}
	return ret;
}

static void __exit
mspec_exit(void)
{
	int nid;

	misc_deregister(&uncached_miscdev);
	misc_deregister(&cached_miscdev);
	if (is_sn2) {
		misc_deregister(&fetchop_miscdev);

		for_each_node(nid) {
			if (scratch_page[nid] != 0)
				uncached_free_page(scratch_page[nid], 1);
		}
	}
}

module_init(mspec_init);
module_exit(mspec_exit);

MODULE_AUTHOR("Silicon Graphics, Inc. <linux-altix@sgi.com>");
MODULE_DESCRIPTION("Driver for SGI SN special memory operations");
MODULE_LICENSE("GPL");
Commit	Line	Data
17a3b050 JS	1	/*
	2	* Copyright (C) 2001-2006 Silicon Graphics, Inc. All rights
	3	* reserved.
	4	*
	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms of version 2 of the GNU General Public License
	7	* as published by the Free Software Foundation.
	8	*/
	9
	10	/*
	11	* SN Platform Special Memory (mspec) Support
	12	*
	13	* This driver exports the SN special memory (mspec) facility to user
	14	* processes.
	15	* There are three types of memory made available thru this driver:
	16	* fetchops, uncached and cached.
	17	*
	18	* Fetchops are atomic memory operations that are implemented in the
	19	* memory controller on SGI SN hardware.
	20	*
	21	* Uncached are used for memory write combining feature of the ia64
	22	* cpu.
	23	*
	24	* Cached are used for areas of memory that are used as cached addresses
	25	* on our partition and used as uncached addresses from other partitions.
	26	* Due to a design constraint of the SN2 Shub, you can not have processors
	27	* on the same FSB perform both a cached and uncached reference to the
	28	* same cache line. These special memory cached regions prevent the
	29	* kernel from ever dropping in a TLB entry and therefore prevent the
	30	* processor from ever speculating a cache line from this page.
	31	*/
	32
17a3b050 JS	33	#include <linux/types.h>
	34	#include <linux/kernel.h>
	35	#include <linux/module.h>
	36	#include <linux/init.h>
	37	#include <linux/errno.h>
	38	#include <linux/miscdevice.h>
	39	#include <linux/spinlock.h>
	40	#include <linux/mm.h>
4e950f6f	41	#include <linux/fs.h>
17a3b050 JS	42	#include <linux/vmalloc.h>
	43	#include <linux/string.h>
	44	#include <linux/slab.h>
	45	#include <linux/numa.h>
f7d88d24	46	#include <linux/refcount.h>
17a3b050	47	#include <asm/page.h>
17a3b050	48	#include <asm/pgtable.h>
60063497	49	#include <linux/atomic.h>
17a3b050 JS	50	#include <asm/tlbflush.h>
	51	#include <asm/uncached.h>
	52	#include <asm/sn/addrs.h>
	53	#include <asm/sn/arch.h>
	54	#include <asm/sn/mspec.h>
	55	#include <asm/sn/sn_cpuid.h>
	56	#include <asm/sn/io.h>
	57	#include <asm/sn/bte.h>
	58	#include <asm/sn/shubio.h>
	59
	60
	61	#define FETCHOP_ID "SGI Fetchop,"
	62	#define CACHED_ID "Cached,"
	63	#define UNCACHED_ID "Uncached"
	64	#define REVISION "4.0"
	65	#define MSPEC_BASENAME "mspec"
	66
	67	/*
	68	* Page types allocated by the device.
	69	*/
4191ba26	70	enum mspec_page_type {
17a3b050 JS	71	MSPEC_FETCHOP = 1,
	72	MSPEC_CACHED,
	73	MSPEC_UNCACHED
	74	};
	75
1a4b0fc5	76	#ifdef CONFIG_SGI_SN
17a3b050	77	static int is_sn2;
1a4b0fc5 JS	78	#else
	79	#define is_sn2 0
	80	#endif
17a3b050 JS	81
	82	/*
	83	* One of these structures is allocated when an mspec region is mmaped. The
	84	* structure is pointed to by the vma->vm_private_data field in the vma struct.
	85	* This structure is used to record the addresses of the mspec pages.
4191ba26 CW	86	* This structure is shared by all vma's that are split off from the
	87	* original vma when split_vma()'s are done.
	88	*
	89	* The refcnt is incremented atomically because mm->mmap_sem does not
	90	* protect in fork case where multiple tasks share the vma_data.
17a3b050 JS	91	*/
17a3b050 JS	92	struct vma_data {
f7d88d24	93	refcount_t refcnt; /* Number of vmas sharing the data. */
4191ba26	94	spinlock_t lock; /* Serialize access to this structure. */
17a3b050	95	int count; /* Number of pages allocated. */
4191ba26	96	enum mspec_page_type type; /* Type of pages allocated. */
4191ba26 CW	97	unsigned long vm_start; /* Original (unsplit) base. */
4191ba26 CW	98	unsigned long vm_end; /* Original (unsplit) end. */
17a3b050 JS	99	unsigned long maddr[0]; /* Array of MSPEC addresses. */
	100	};
	101
	102	/* used on shub2 to clear FOP cache in the HUB */
	103	static unsigned long scratch_page[MAX_NUMNODES];
	104	#define SH2_AMO_CACHE_ENTRIES 4
	105
	106	static inline int
	107	mspec_zero_block(unsigned long addr, int len)
	108	{
	109	int status;
	110
	111	if (is_sn2) {
	112	if (is_shub2()) {
	113	int nid;
	114	void *p;
	115	int i;
	116
	117	nid = nasid_to_cnodeid(get_node_number(__pa(addr)));
	118	p = (void *)TO_AMO(scratch_page[nid]);
	119
	120	for (i=0; i < SH2_AMO_CACHE_ENTRIES; i++) {
	121	FETCHOP_LOAD_OP(p, FETCHOP_LOAD);
	122	p += FETCHOP_VAR_SIZE;
	123	}
	124	}
	125
	126	status = bte_copy(0, addr & ~__IA64_UNCACHED_OFFSET, len,
	127	BTE_WACQUIRE \| BTE_ZERO_FILL, NULL);
	128	} else {
	129	memset((char *) addr, 0, len);
	130	status = 0;
	131	}
	132	return status;
	133	}
	134
	135	/*
	136	* mspec_open
	137	*
	138	* Called when a device mapping is created by a means other than mmap
4191ba26 CW	139	* (via fork, munmap, etc.). Increments the reference count on the
4191ba26 CW	140	* underlying mspec data so it is not freed prematurely.
17a3b050 JS	141	*/
	142	static void
	143	mspec_open(struct vm_area_struct *vma)
	144	{
	145	struct vma_data *vdata;
	146
	147	vdata = vma->vm_private_data;
f7d88d24	148	refcount_inc(&vdata->refcnt);
17a3b050 JS	149	}
	150
	151	/*
	152	* mspec_close
	153	*
	154	* Called when unmapping a device mapping. Frees all mspec pages
afa684f6	155	* belonging to all the vma's sharing this vma_data structure.
17a3b050 JS	156	*/
	157	static void
	158	mspec_close(struct vm_area_struct *vma)
	159	{
	160	struct vma_data *vdata;
afa684f6	161	int index, last_index;
4191ba26	162	unsigned long my_page;
17a3b050 JS	163
17a3b050 JS	164	vdata = vma->vm_private_data;
17a3b050	165
f7d88d24	166	if (!refcount_dec_and_test(&vdata->refcnt))
afa684f6	167	return;
4191ba26	168
afa684f6 CW	169	last_index = (vdata->vm_end - vdata->vm_start) >> PAGE_SHIFT;
afa684f6 CW	170	for (index = 0; index < last_index; index++) {
4191ba26	171	if (vdata->maddr[index] == 0)
17a3b050 JS	172	continue;
	173	/*
	174	* Clear the page before sticking it back
	175	* into the pool.
	176	*/
4191ba26 CW	177	my_page = vdata->maddr[index];
4191ba26 CW	178	vdata->maddr[index] = 0;
afa684f6	179	if (!mspec_zero_block(my_page, PAGE_SIZE))
e4a064df	180	uncached_free_page(my_page, 1);
17a3b050 JS	181	else
17a3b050 JS	182	printk(KERN_WARNING "mspec_close(): "
afa684f6	183	"failed to zero page %ld\n", my_page);
17a3b050	184	}
4191ba26	185
1d5cfdb0	186	kvfree(vdata);
17a3b050 JS	187	}
17a3b050 JS	188
17a3b050	189	/*
efe9e779	190	* mspec_fault
17a3b050 JS	191	*
	192	* Creates a mspec page and maps it to user space.
	193	*/
3eb87d4e	194	static vm_fault_t
11bac800	195	mspec_fault(struct vm_fault *vmf)
17a3b050 JS	196	{
	197	unsigned long paddr, maddr;
	198	unsigned long pfn;
efe9e779	199	pgoff_t index = vmf->pgoff;
11bac800	200	struct vma_data *vdata = vmf->vma->vm_private_data;
17a3b050	201
17a3b050 JS	202	maddr = (volatile unsigned long) vdata->maddr[index];
17a3b050 JS	203	if (maddr == 0) {
e4a064df	204	maddr = uncached_alloc_page(numa_node_id(), 1);
17a3b050	205	if (maddr == 0)
efe9e779	206	return VM_FAULT_OOM;
17a3b050 JS	207
	208	spin_lock(&vdata->lock);
	209	if (vdata->maddr[index] == 0) {
	210	vdata->count++;
	211	vdata->maddr[index] = maddr;
	212	} else {
e4a064df	213	uncached_free_page(maddr, 1);
17a3b050 JS	214	maddr = vdata->maddr[index];
	215	}
	216	spin_unlock(&vdata->lock);
	217	}
	218
	219	if (vdata->type == MSPEC_FETCHOP)
	220	paddr = TO_AMO(maddr);
	221	else
1a4b0fc5	222	paddr = maddr & ~__IA64_UNCACHED_OFFSET;
17a3b050 JS	223
	224	pfn = paddr >> PAGE_SHIFT;
	225
3eb87d4e	226	return vmf_insert_pfn(vmf->vma, vmf->address, pfn);
17a3b050 JS	227	}
17a3b050 JS	228
f0f37e2f	229	static const struct vm_operations_struct mspec_vm_ops = {
17a3b050 JS	230	.open = mspec_open,
17a3b050 JS	231	.close = mspec_close,
efe9e779	232	.fault = mspec_fault,
17a3b050 JS	233	};
	234
	235	/*
	236	* mspec_mmap
	237	*
af901ca1	238	* Called when mmapping the device. Initializes the vma with a fault handler
17a3b050 JS	239	* and private data structure necessary to allocate, track, and free the
	240	* underlying pages.
	241	*/
	242	static int
4191ba26 CW	243	mspec_mmap(struct file file, struct vm_area_struct vma,
4191ba26 CW	244	enum mspec_page_type type)
17a3b050 JS	245	{
17a3b050 JS	246	struct vma_data *vdata;
1d5cfdb0	247	int pages, vdata_size;
17a3b050 JS	248
	249	if (vma->vm_pgoff != 0)
	250	return -EINVAL;
	251
	252	if ((vma->vm_flags & VM_SHARED) == 0)
	253	return -EINVAL;
	254
	255	if ((vma->vm_flags & VM_WRITE) == 0)
	256	return -EPERM;
	257
a0ea59d5	258	pages = vma_pages(vma);
17a3b050 JS	259	vdata_size = sizeof(struct vma_data) + pages * sizeof(long);
17a3b050 JS	260	if (vdata_size <= PAGE_SIZE)
658c74cf	261	vdata = kzalloc(vdata_size, GFP_KERNEL);
1d5cfdb0	262	else
658c74cf	263	vdata = vzalloc(vdata_size);
17a3b050 JS	264	if (!vdata)
17a3b050 JS	265	return -ENOMEM;
17a3b050	266
4191ba26 CW	267	vdata->vm_start = vma->vm_start;
4191ba26 CW	268	vdata->vm_end = vma->vm_end;
17a3b050 JS	269	vdata->type = type;
17a3b050 JS	270	spin_lock_init(&vdata->lock);
f7d88d24	271	refcount_set(&vdata->refcnt, 1);
17a3b050 JS	272	vma->vm_private_data = vdata;
17a3b050 JS	273
314e51b9	274	vma->vm_flags \|= VM_IO \| VM_PFNMAP \| VM_DONTEXPAND \| VM_DONTDUMP;
17a3b050 JS	275	if (vdata->type == MSPEC_FETCHOP \|\| vdata->type == MSPEC_UNCACHED)
	276	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
	277	vma->vm_ops = &mspec_vm_ops;
	278
	279	return 0;
	280	}
	281
	282	static int
	283	fetchop_mmap(struct file file, struct vm_area_struct vma)
	284	{
	285	return mspec_mmap(file, vma, MSPEC_FETCHOP);
	286	}
	287
	288	static int
	289	cached_mmap(struct file file, struct vm_area_struct vma)
	290	{
	291	return mspec_mmap(file, vma, MSPEC_CACHED);
	292	}
	293
	294	static int
	295	uncached_mmap(struct file file, struct vm_area_struct vma)
	296	{
	297	return mspec_mmap(file, vma, MSPEC_UNCACHED);
	298	}
	299
2b8693c0	300	static const struct file_operations fetchop_fops = {
17a3b050	301	.owner = THIS_MODULE,
6038f373 AB	302	.mmap = fetchop_mmap,
6038f373 AB	303	.llseek = noop_llseek,
17a3b050 JS	304	};
	305
	306	static struct miscdevice fetchop_miscdev = {
	307	.minor = MISC_DYNAMIC_MINOR,
	308	.name = "sgi_fetchop",
	309	.fops = &fetchop_fops
	310	};
	311
2b8693c0	312	static const struct file_operations cached_fops = {
17a3b050	313	.owner = THIS_MODULE,
6038f373 AB	314	.mmap = cached_mmap,
6038f373 AB	315	.llseek = noop_llseek,
17a3b050 JS	316	};
	317
	318	static struct miscdevice cached_miscdev = {
	319	.minor = MISC_DYNAMIC_MINOR,
	320	.name = "mspec_cached",
	321	.fops = &cached_fops
	322	};
	323
2b8693c0	324	static const struct file_operations uncached_fops = {
17a3b050	325	.owner = THIS_MODULE,
6038f373 AB	326	.mmap = uncached_mmap,
6038f373 AB	327	.llseek = noop_llseek,
17a3b050 JS	328	};
	329
	330	static struct miscdevice uncached_miscdev = {
	331	.minor = MISC_DYNAMIC_MINOR,
	332	.name = "mspec_uncached",
	333	.fops = &uncached_fops
	334	};
	335
	336	/*
	337	* mspec_init
	338	*
	339	* Called at boot time to initialize the mspec facility.
	340	*/
	341	static int __init
	342	mspec_init(void)
	343	{
	344	int ret;
	345	int nid;
	346
	347	/*
	348	* The fetchop device only works on SN2 hardware, uncached and cached
	349	* memory drivers should both be valid on all ia64 hardware
	350	*/
1a4b0fc5	351	#ifdef CONFIG_SGI_SN
17a3b050 JS	352	if (ia64_platform_is("sn2")) {
	353	is_sn2 = 1;
	354	if (is_shub2()) {
	355	ret = -ENOMEM;
2dca53a9	356	for_each_node_state(nid, N_ONLINE) {
17a3b050 JS	357	int actual_nid;
	358	int nasid;
	359	unsigned long phys;
	360
e4a064df	361	scratch_page[nid] = uncached_alloc_page(nid, 1);
17a3b050 JS	362	if (scratch_page[nid] == 0)
	363	goto free_scratch_pages;
	364	phys = __pa(scratch_page[nid]);
	365	nasid = get_node_number(phys);
	366	actual_nid = nasid_to_cnodeid(nasid);
	367	if (actual_nid != nid)
	368	goto free_scratch_pages;
	369	}
	370	}
	371
	372	ret = misc_register(&fetchop_miscdev);
	373	if (ret) {
	374	printk(KERN_ERR
	375	"%s: failed to register device %i\n",
	376	FETCHOP_ID, ret);
	377	goto free_scratch_pages;
	378	}
	379	}
1a4b0fc5	380	#endif
17a3b050 JS	381	ret = misc_register(&cached_miscdev);
	382	if (ret) {
	383	printk(KERN_ERR "%s: failed to register device %i\n",
	384	CACHED_ID, ret);
	385	if (is_sn2)
	386	misc_deregister(&fetchop_miscdev);
	387	goto free_scratch_pages;
	388	}
	389	ret = misc_register(&uncached_miscdev);
	390	if (ret) {
	391	printk(KERN_ERR "%s: failed to register device %i\n",
	392	UNCACHED_ID, ret);
	393	misc_deregister(&cached_miscdev);
	394	if (is_sn2)
	395	misc_deregister(&fetchop_miscdev);
	396	goto free_scratch_pages;
	397	}
	398
	399	printk(KERN_INFO "%s %s initialized devices: %s %s %s\n",
	400	MSPEC_BASENAME, REVISION, is_sn2 ? FETCHOP_ID : "",
	401	CACHED_ID, UNCACHED_ID);
	402
	403	return 0;
	404
	405	free_scratch_pages:
	406	for_each_node(nid) {
	407	if (scratch_page[nid] != 0)
e4a064df	408	uncached_free_page(scratch_page[nid], 1);
17a3b050 JS	409	}
	410	return ret;
	411	}
	412
	413	static void __exit
	414	mspec_exit(void)
	415	{
	416	int nid;
	417
	418	misc_deregister(&uncached_miscdev);
	419	misc_deregister(&cached_miscdev);
	420	if (is_sn2) {
	421	misc_deregister(&fetchop_miscdev);
	422
	423	for_each_node(nid) {
	424	if (scratch_page[nid] != 0)
e4a064df	425	uncached_free_page(scratch_page[nid], 1);
17a3b050 JS	426	}
	427	}
	428	}
	429
	430	module_init(mspec_init);
	431	module_exit(mspec_exit);
	432
	433	MODULE_AUTHOR("Silicon Graphics, Inc. <linux-altix@sgi.com>");
	434	MODULE_DESCRIPTION("Driver for SGI SN special memory operations");
	435	MODULE_LICENSE("GPL");